The Doctor is called in to investigate a pair of mysterious seed pods in the Antarctic. As the Doctor looks to uncover their mysteries, a ruthless collector arrives to add the seeds to his menagerie. Things take a turn when it is discovered that the pods harbor intelligent life with sinister plans of its own.

Sunday

The TARDIS picks up a distress call and the Doctor and Sarah arrive on the planet Zeta Minor. There they discover that a Morestran geological expedition has fallen prey to an unseen killer and only the leader, Professor Sorenson, remains alive.

The Doctor is called in to investigate a pair of mysterious seed pods in the Antarctic. As the Doctor looks to uncover their mysteries, a ruthless collector arrives to add the seeds to his menagerie. Things take a turn when it is discovered that the pods harbor intelligent life with sinister plans of its own.